Factors controlling generation and propagation of pacemaker potentials in network models of mammalian SA node

Large-scale, biophysically detailed network models of the SA node and atrium are developed on the CM-5 parallel supercomputer. The models are used to investigate three factors controlling the site of generation and propagation of the cardiac pacemaker potential: a) magnitude of cell-to-cell gap junction coupling in the SA node; b) spatial variation of membrane current density in SA node; and c) interdigitation of SA node and atrial tissue.